A PET scan is an imaging test that shows metabolic activity in the body, but it does not directly show the cancer stage.
As someone who has lost a dear family pet to cancer, I know the anxiety around determining the stage and severity of the disease.
Like us, our furry friends can develop dangerous cancers that require accurate staging for proper treatment.
One test we may consider is a PET scan which is an online pet product, but does a PET scan show what stage cancer is in pets or people?
Unfortunately, the answer is not so straightforward. A PET scan alone does not directly identify the stage or progression of cancer.
However, it is an invaluable imaging tool that shows metabolic activity and can help identify whether cancer may have spread to other areas of the body. This information aids clinicians in determining the cancer stage.
How PET Scans Work
So how does a PET scan work, and what can it tell us?
- PET stands for Positron Emission Tomography.
- A small amount of radioactive tracer is injected into the patient’s body, which accumulates in areas with high metabolic activity like cancer cells.
- The PET scanner detects emissions from the tracer, creating 3D images showing where the substance accumulated.
- Areas of disease “light up” on the scan if they are metabolically active and accumulating the tracer.
So in cancers with increased metabolic activity, PET scans can identify primary tumors and areas where cancer may have spread, known as metastases.
It does this better than many other imaging tests like CT or MRI scans. This is extremely helpful in determining the stage.
PET Scans and Cancer Staging
Cancer staging relies on determining the size and location of the primary tumor, whether it has grown into nearby tissues, and if it has spread to lymph nodes or other organs.
- While a PET scan does not directly identify the size of the primary tumor, it can reveal areas of suspicion that need further testing.
- It is excellent at mapping lymph node involvement and detecting metastases, which directly impact staging.
For example, finding multiple sites of disease spread on a PET scan would indicate advanced stage 3 or 4 cancer.
The detection of lymph node involvement can differentiate between early and late-stage disease.
So in summary, while PET scans do not directly or independently determine cancer stage, they are an invaluable tool in mapping disease spread and aiding clinical stage determination.
The metabolic information they provide complements anatomical imaging and physical exams to provide a complete picture.
Should You Get A Pet Scan for Cancer?
Given the useful metabolic information they provide, PET scans are often recommended during the initial cancer staging process and to monitor treatment response. They can detect disease relapse or progression sooner than other methods in some cases.
PET scans are particularly helpful for staging lymphomas, lung cancer, colorectal cancer, head and neck cancers, melanoma, and many other malignancies.
That said, PET scans are not recommended for all purposes, such as screening average-risk individuals with no symptoms.
They are also not the first choice for staging some cancer types like prostate cancer. Your oncologist can help decide if a PET scan is appropriate for your specific situation.
